Eu tenho uma classe de caso que se parece com isso:

case class Color(name: String, red: Int, green: Int, blue: Int)

Estou usando Shapeless 2.3.1 com Scala 2.11.8. Estou vendo um comportamento diferente do meu teste e do REPL em termos de encontrar o valor implícito paraLabelledGeneric[Color]. (Na verdade, estou tentando derivar automaticamente outras classes, mas estou recebendonull por isso também)

Teste interno

package foo

import shapeless._
import org.specs2.mutable._

case class Color(name: String, red: Int, green: Int, blue: Int)

object CustomProtocol {
  implicit val colorLabel: LabelledGeneric[Color] = LabelledGeneric[Color]
}

class GenericFormatsSpec extends Specification {
  val color = Color("CadetBlue", 95, 158, 160)

  "The case class example" should {
    "behave as expected" in {
      import CustomProtocol._
      assert(colorLabel != null, "colorLabel is null")
      1 mustEqual 1
    }
  }
}

Este teste falha porquecolorLabel énull. Por quê?

REPL

No REPL, posso encontrarLabelledGeneric[Color]:

scala> case class Color(name: String, red: Int, green: Int, blue: Int)
defined class Color

scala> import shapeless._
import shapeless._

scala> LabelledGeneric[Color]
res0: shapeless.LabelledGeneric[Color]{type Repr = shapeless.::[String with shapeless.labelled.KeyTag[Symbol with shapeless.tag.Tagged[String("name")],String],shapeless.::[Int with shapeless.labelled.KeyTag[Symbol with shapeless.tag.Tagged[String("red")],Int],shapeless.::[Int with shapeless.labelled.KeyTag[Symbol with shapeless.tag.Tagged[String("green")],Int],shapeless.::[Int with shapeless.labelled.KeyTag[Symbol with shapeless.tag.Tagged[String("blue")],Int],shapeless.HNil]]]]} = shapeless.LabelledGeneric$anon$1@755f11d9